The present disclosure relates generally to well drilling operations and, more particularly, to a method and apparatus for optimizing deep resistivity measurements with multi-component antennas.
Well drilling operations typically require surveys and measurements to determine formation boundary conditions. These surveys and measurements may be essential to targeting particular formation strata. In certain instances, the surveys or measurements may use near-bit sensors to “look-ahead” of the bit to determine a formation resistivity, which can be used to determine formation boundaries through the use of inversion techniques. The accuracy of resistivity measurements, and therefore the accuracy of the boundary determinations, is largely dependant on formation anisotropy. Formation anisotropy may be associated with laminated sediments that produce a horizontal resistivity (Rh) in a direction parallel to the formation plane that is different from, and typically lower than, a vertical resistivity (Rv) in a direction perpendicular to the formation plane. The presence of formation anisotropy may alter the “look-ahead” signals, leading to a misinterpretation of the formation geology unless computationally intensive and costly inversion techniques and models are used to account for the anisotropy effects.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.